THE CANADIAN ENTOMOLOGIST. 19 



NOTES ON THE AMERICAN FORMS OF t:UCHLOE, HUBN. 



BY A. G. BQTLER, PH. D., BRITISH MUSEUM, LONDON, ENGLAND. 



Dr. Beutenrnuller, in his recent revision of the species of Etichloe, 

 notes the fact that the neuration of this genus is variable, but he appears 

 not to have been aware that the variation is so frequent that no division 

 of the genus based thereupon has any vaUie. In his three groups, 

 Euch/oe, Midea and Aut/io:haris, there are not only species differing in 

 the number of veins in the primaries, but individuals of the same species 

 differ in the same way. 



Another point in Dr. Beutenmuller's definition of his groups requires 

 consideration ; he speaks of vein 9 as being present or absent, whereas 

 a careful examination of the position of the veins must make it evident 

 that vein 9 is never absent, but that veins 7 and 8 frequently coalesce or 



are conterminous. This is quite certain, from the fact that in all species 

 which normally possess 1 1 veins only in the primaries, the twelfth vein 

 occurs abnormally as a furcation of vein 7 : thus, in Midea lanceolata, 

 which usually has only eleven veins, vein 7 is sometimes forked near the 

 distal extremity, though with a shorter fork than is usually seen in 

 Euchloe Sara ; nevertheless, some examples of the latter, and particularly 

 in the smaller varieties, E. Feakirtii diUd Julia, have only ir veins. 



Dr. Beutenmuller places E. pima and E. meihtira under Midea, 

 although, excepting in the absence of the fork to vein 7 (or, in other 

 words, in the absence of vein 8), they agree far more closely with the 

 species o{ Zegris. 



Some of the white species oi Euchloe have 11 and others have 12 

 veins to the primaries, whilst the second subcostal branch (vein 10) 

 varies considerably in its position in the same species, being emitted 

 before, at or after the end of the discoidal cell. 



/Vs regards E. creusa, I believe it to vary seasonally as much as its 

 very close ally, E. ausonia; the attempt to distinguish between E. 

 ausonides and E. hyantis looks to me like a failure, not that they cannot 

 be readily distinguished by size, form of secondaries, depth of ground- 

 tint, and size of white spots on under surface, but because these differ- 

 ences are also to be seen in undoubted seasonal variations of the 

 European form, E. ausonia, and because if E. ausonides is distinct from 

 E. hyantis, the Vancouver form, which differs in the pattern of the under 

 surface, has an equal claim to separation. As regards typical E. creusa, 

 which Dr. Beutenmiiller considers to be E. hyantis, I can definitely 

 assure him that the type (which we possess) agrees with his var. elsa. 



My idea of this species is that it can be arbitrarily sorted out into 

 seven graded forms ; E. ausonides, E. var. from Vancouver, E. hyantis, 

 E. lotta, E. coloradensis, E. creusa = elsa. 



Euchloe olympia is undoubtedly a species of Zegris. 



